2011 GMC SIERRA TRUCK BOX, Off of a Staff Taxi and the inside measurement of the box is 5.75'. It will suit all GMC & & CHEVY Trucks within a few years in either case of the 2011 including the Denali Truck. It is in exceptional form (Box, Tailgate with vital, Tail Lights & & Black Paint). Asking 1400 obo. Call James anytime at -LRB-604-RRB- 868-4708.